1. Field of the Invention
The invention relates to a self-propelled inspection vehicle for piping installations, including a vehicle body and a propulsion mechanism resiliently bracing the vehicle body against the inside surface of the pipe.
2. Description of the Prior Art
A self-propelled inspection vehicle which is known in the prior art is constructed as an equipment carrier and is braced by several wheels against the inside wall surface of a pipe to be inspected. In this conventional inspection vehicle, the length of the vehicle body is several times the inside diameter of the pipe to be negotiated. The vehicle body is constructed as an articulated support body with gimbal action, so that narrow pipe elbows can also be travelled. In this self-propelled inspection vehicle, the drive energy must be supplied through a cable which must be dragged along. It is inherent in this inspection vehicle that its range of action is limited already because of the friction resistance of the cable to be dragged along on the walls of the pipe. The friction increases with increasing distance from the starting point. This friction force increases especially after negotiating several pipe elbows or if the inspection vehicle must negotiate vertical pipe sections and then must also lift the weight of the vertically hanging section of the cable, besides its own weight and the friction resistance of the cable to be dragged along.